Method for solid solution hardening of cold-deformed workpiece of passive alloy and solid solution hardened member by this method

摘要

The invention relates to a method for method for solution hardening of a cold deformed workpiece of a passive alloy containing at least 10% chromium, which method comprises -dissolving at least nitrogen in the workpiece at a temperature T1, which is higher than the solubility temperature for carbide and/or nitride and lower than the melting point of the passive alloy, wherein dissolution of nitrogen at temperature T1 is performed to obtain a diffusion depth in the range of 0 mum to 5 mm, and -cooling the workpiece after the dissolution step at temperature T1 to a temperature which is lower than the temperature at which carbides and/or nitrides form in the passive alloy, wherein the cooling step takes place in an inert gas not containing nitrogen. The invention further relates to a member, such as a lock washer for securing bolts or nuts prepared using the method.